Notebook[List[Cell[BoxData[FormBox[RowBox[List[RowBox[List["E", "(", "x", ")"]], "=", RowBox[List[FractionBox["1", "2"], RowBox[List[UnderscriptBox["\[Sum]", RowBox[List[RowBox[List["(", RowBox[List["i", ",", "j"]], ")"]], "\[Element]", "\[CurlyEpsilon]"]]], RowBox[List[SubscriptBox["k", "ij"], SuperscriptBox[RowBox[List["\[LeftDoubleBracketingBar]", RowBox[List[SubscriptBox["x", "i"], "-", SubscriptBox["x", "j"], "-", SubscriptBox["d", "ij"]]], "\[RightDoubleBracketingBar]"]], "2"]]]]]]]]], TraditionalForm]], "Input"]]]